This invention pertains generally to telephone communication equipment, and more particularly to interfacing new network interface capabilities to telephone switching equipment.
Telephone service for a small business or the like is typically provided by installing a switching unit (e.g., a Private Branch Exchange (PBX), a Key Switching Unit (KSU), etc.) at the business premises, connecting a plurality of telephone terminal devices located on the business premises to the switching unit, and connecting the switching unit to a telephone network. All of the equipment located at the telephone customer location is known generally as Customer Premises Equipment (CPE).
The switching unit typically includes drivers for interfacing services available on the telephone network to the local terminal devices, an example of which is shown in FIG. 1. A CPE switching unit 1 has a plurality of CPE terminals 2 connected into the switching unit""s switching fabric 3. Switching fabric 3 connects the terminals 2 to communication networks by means well known in the art and not shown. Switching unit 1 connects via a network interface communication channel 4 to network interface 5 which interfaces to network 6. Network 6 might be the Public Switched Telephone Network (PSTN), in which case network interface 5 might consist of switching equipment at the telephone company central office. The exemplary switching unit I includes a network interface template 12, which is an abstraction layer specifying the functional intelligence related to network interface communication channel 4. The abstraction layer contained in network interface template 12 should be substantially independent of the actual hardware interface. Network interface driver 14 interfaces CPE switching unit 1 with network interface communication channel 4. Network interface driver 14 is informed by network interface template 12 as to the capabilities of network interface communication channel 4, and for this purpose communicates with network interface 12 by means of interface 13. Network interface template 12 and network interface driver 14 typically are heavily software-implemented, and therefore interface 13 typically comprise shared memory areas or data transfers internal to the platform on which network interface template 12 and network interface driver 14 are resident. To make the abstraction layer represented by network interface template 12 substantially independent of network interface hardware, interface 13 is an abstracting layer, signalling network interface driver 14""s hardware-related functions according to the abstract definitions of those functions conveyed by network interface template 12.
As new services become available on telephone networks or as it is desired to provide new services to users, appropriate drivers must be interfaced to the switching unit accordingly. Building a new driver into the switching unit (e.g., an xe2x80x9cembedded driverxe2x80x9d) necessitates a new design of the switching unit, which requires a long lead time for design and manufacturing. Also, it may be desired to provide a new service through an existing switching unit.
There is thus a need for interfacing non-embedded drivers (i.e., drivers resident on external platforms) to communication switching units.
Accordingly it is an object of the present invention to provide improved methods and systems for interfacing non-embedded drivers to communication switching units.
It is another object of the present invention to provide methods and system for interfacing non-embedded drivers to communication switching units while isolating the driver from hardware details of the switching units.
It is another object of the present invention to foster an open architecture for communication switching units wherein third-party vendors may develop new drivers.
These and other objects of the invention will become apparent to those skilled in the art from the following description thereof.
In accordance with the teachings of the present invention, these and other objects may be accomplished by the present systems and methods of adding non-embedded network interface drivers to a telephone communication switch while minimizing impact on the switch. A proxy driver which presents the appearance of a network interface driver is embedded in the switch. An external hardware platform containing the non-embedded driver is connected to the proxy driver. The external hardware platform includes a proxy interface coupled to the proxy driver. The proxy driver communicates with the switch""s internal network intelligence via a virtual device interface, and sends signals derived from the virtual device interface to the proxy interface, which in turn replicates the switch""s virtual device interface in the external hardware platform. The replicate in the external platform of the switch""s virtual device interface permits the non-embedded driver to interface closely with internal network intelligence of the switch despite being isolated from hardware details of the switch thus fostering an open architecture for non-embedded drivers.